Shares of Dollar General (DG -3.79%) took a 9% hit on Tuesday after the company hosed down its guidance for the full fiscal year. The report follows disappointing results last month out of Wal-Mart (WMT 0.03%) and Target (TGT -0.65%).

In this video, longtime Fool contributor Rick Munarriz explains why this is a problematic trend -- and why Dollar General is actually holding up better than Wal-Mart and Target despite the more pronounced sell-off.